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A Review of the Li-ion Battery in-situ Experiments in Scanning Electron Microscope
Trochta, David ; Klvač, Ondřej ; Kazda, Tomáš
This paper focuses on the description of in-situ experiments with lithium-ion batteries in a scanning electron microscope during cycling. With these experiments, we are able to better understand the working principles and internal processes of Li-ion batteries and improve their efficiency, reliability, and safety based on this knowledge. However, conducting these experiments poses several challenges, which are described in the paper, along with ways in which they can be partially mitigated.
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Manufacturing of Motorcycle Sprocket
Hrazdíra, Michal ; Podaný, Kamil (referee) ; Řiháček, Jan (advisor)
The work focuses on the production of a motorcycle sprocket, which transfers the torque from the output shaft of the gearbox to the rear disk of the wheel. Steel 12 050 was chosen for the production of the component, which is suitable for the intended purpose. The sprocket, produced in a series of 80,000 pieces per year, has a diameter of 191.9 mm and a thickness of 5 mm. After considering all factors, fine blanking with v-ring was selected as the manufacturing method. For this series, a semi-finished product in the form of a coil was chosen, which has an outer diameter of 1,400 mm and a width of 204 mm. For the annual production batch, 59 full coils and one incomplete coil will be required. Before the actual tool design, technological and control calculations were performed to verify the functionality of the proposed cutter. The tool was supplemented with technical documentation and a detailed description of the construction. Based on the calculated values, a triple-action hydraulic press Feintool HFA 11,000 plus was designed, which is part of the production line, which also includes decoiling and straightening equipment.
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The Memoirs of Frank McCourt: An Analysis
ROSSMÜLLEROVÁ, Denisa
After a brief introduction of the Irish American author Frank McCourt and his memoirs Angela's Ashes (1996), 'Tis (1999), and Teacher Man (2005), this thesis presents the main issues with McCourt's memoirs and the opinions of the critics while also exploring the reason for its overwhelming success across the general public as well as the academic environment. The three memoirs are then briefly introduced, commented on and a detailed summary with quotes is provided for each of them. The thesis is concluded with a summary of discovered notions regarding the analyzed memoirs.
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Protection of data transmission against long error bursts
Malach, Roman ; Lambertová, Petra (referee) ; Němec, Karel (advisor)
This Master´s thesis discuses the protection of data transmission against long error bursts. The data is transmited throught the channel with defined error rate. Parameters of the channel are error-free interval 2000 bits and length of burst error 250 bits. One of the aims of this work is to make a set of possible methods for the realization of a system for data correction. The basic selection is made from most known codes. These codes are divided into several categories and then the best one is chosen for higher selection. Of course interleaving is used too. Only one code from each category can pass on to the higher level of the best code selection. At the end the codes are compared and the best three are simulated using the Matlab program to check correct function. From these three options, one is chosen as optimal regarding practical realization. Two options exist, hardware or software realization. The second one would seem more useful. The real codec is created in validator language C. Nowadays, considering language C and from a computer architecture point of view the 8 bits size of element unit is convenient. That´s why the code RS(255, 191), which works with 8 bits symbols, is optimal. In the next step the codec of this code is created containing the coder and decoder of the code above. The simulation of error channel is ensured by last program. Finally the results are presented using several examples.
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Perfect Hashing in FPGA
Matušová, Lucie ; Košař, Vlastimil (referee) ; Kaštil, Jan (advisor)
This thesis deals with a design and implementation of a perfect hashing in FPGA by using an FCH method. The method requires 2.6 bits per key to be stored. For the purposes of reference implementation the CMPH library has been used. The functionality of the implemented unit was verified in simulations by the program ModelSim and by experiments on ML605 board bedded with Virtex-6 chip. An experimental part of this work applies to an analysis of enhancement possibilities of the frequency unit. Maximum achieved frequency is 191 MHz. Possible directions of this work are discussed in the conclusion.
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Production of lamp cover
Tóthová, Romana ; Lidmila, Zdeněk (referee) ; Podaný, Kamil (advisor)
Project dissertate about manufacturing of lamp cover of steel 13 200 in serie 43 000. After comparing all the alternatives how to make the product , was choose a method of convention deep drawing. Product is manufactured in one operation. Design of apparatus using as standardized, so special parts. It is fitted in hydraulic pressing machine CTC 25. Functional parts are made from tool steel 19 191. Costs of production was calculated on 15,21 crowns a piece. From 26 173 manufactured pieces will the production gainful.
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Study of phenolic compounds in some biologic materials using method LC/MS
Měřínská, Radana ; Zemanová, Jana (referee) ; Kočí, Radka (advisor)
Presented bachelor thesis was focused on suitable methods for analysis of phenolics, especially modern instrumental methods were studied. In experimental part some standard phenolic compounds were analysed using combined technique HPLC/ESI-MS with off-line and/or on-line detection. Mass spectra of individual stadards and/or mixtures were determined in MS full scan and/or MS/MS full scan mode. Ionisation of chosen standard compounds was done in pozitive and/or negative mode. Parent ions of followed compounds were identified: reserpine (PI 609.9, NI 607.7), acid chlorogenic (NI 353), quercetin (PI 303.5, NI 301.5), rutin (PI 611, NI 609), morin (PI 303.1, NI 301.1). Typical fragments of studied standards were produced using MS/MS full scan mode. By fragmentation characteristic product ions were identified: acid chlorogenic (NI 191), quercetin (PI: 229.1 and 257.1; NI: 179.0 and 151.0), rutin (in MS/MS NI: 301; in MS3 NI: 179, 151.1), morin (PI: 285.1 a 257.1; NI: 283.2, 273.2, 257.1, 229.1). Optimal conditions of phenolic HPLC separation were determined including gradient elution and Restek column use. In conclusion on-line HPLC/MS detection using negative ionization was observed as the best configuration for phenolic analysis.
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Control of dividing attachment
Španěl, Petr ; Procházka, Petr (referee) ; Huták, Petr (advisor)
Automatic cutting machine can cut wires and cables to user-defined length at a specified number of pieces. These equipments are usually custom-made for needs of the requested application and they are not very spread out tools on the Czech market. This described device is specified for efficiency-rise in the production of heat-resistant cables. These prepared cables are used for internal connection of the resistors.
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Energy efficient mountain chalet
Hartman, František ; Vlach, František (referee) ; Bečkovský, David (advisor)
This diploma thesis deals with project energy efficient mountain chalet. The building is located in the Krkonoše national park, near by highest Czech mountain named Sněžka. Object is located on plot number 899 in the cadastral Pec pod Sněžkou, on the site of the initial ,,Giant” chalet. The aim of this thesis is proposal of energy efficient mountain chalet in extreme climate conditions, such as in the mountain area, at the elevation 1378 m. Proposal of the chalet emphasis is on achieving maximum energy self-sufficiency. The building consists of two objects SO 01 and SO 02 interconnected by the roof. The total built-up area is 191.39 square meters. The accommodation capacity is 20 people.
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Generation of volatile zinc chelates from aqueous matrix
Kračmarová, Aneta ; Nováková, Eliška (advisor) ; Červený, Václav (referee)
The topic of this work was optimization of the conditions for the generation of volatile zinc chelates. The aim was to develop an alternative method for generating volatile Zn speciates to its reduction by sodium tetrahydridoborate. Detection was carried out by atomic absorption spectrometry. Optimization of the conditions of the chelation reaction itself included the selection of a suitable chelating agent and appropriate modifiers, pH adjustment, suitable reagent and carrier gas flow rates, and appropriate apparatus arrangement. The following method characteristics were obtained under optimal conditions: LOD 1.55 mg L-1 , LOQ 5.17 mg L-1 and sensitivity 0.245 s L mg-1 . The repeatability was 13,7 %. The addition of modifiers was then tested to increase the efficiency of generation of volatile zinc chelates. Potential modifiers included transition metals, organic solvents, heterocyclic organic compounds, compounds from the carbamate group and surfactants. The heterocyclic 1,10-phenanthroline and the carbamate NaPDC were included in the optimal conditions because without them it was not possible to distinguish the signal from noise. Acetonitrile proved to be the most effective modifier, increasing the efficiency to 1547 %. With the addition of acetonitrile, the LOD decreased to 0.191 mg L-1 , the...
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